valid name

例句：

1. 1.The new policy is valid for the next six months.
   这项新政策有效期为六个月。
2. 2.The test results are valid only if they meet certain criteria.
   测试结果只有在满足一定标准时才有效。
3. 3. The contract is valid until the end of the year.
   合同有效期至年底。